Nikon D780 DSLR Camera (Body Only) - Manual (Page 187)

141 Shooting Settings
A Predictive Focus Tracking
If AF-C is selected for AF mode, or if AF-A is selected and the camera is
shooting using AF-C , the camera will initiate predictive focus tracking if
the subject moves toward or away from the camera while the shutter-
release button is pressed halfway or the
AF-ON button is pressed. This
allows the camera to track focus while attempting to predict where the
subject will be when the shutter is released.